Computing devices use various forms of human interface devices. Most computers include some form of display to present information visually to a user. In addition, most computers have one or more user input devices. Keyboards and mice are widely used input devices for desktop computers.
For computers that are more mobile, the functions of the output and input devices can be combined into a touch sensitive display. Such a display can render output as in a traditional computer. In addition, portions of the screen can be associated with control functions. When a user touches a designated portion of the screen, the computer interprets the touch as user input activating that control.
Many computers with touch sensitive displays, particularly those without separate keyboards for receiving user input, can be controlled to display a keyboard. When the user presses on the display screen where a key of the keyboard is pictured, the computer interprets that detected input in the same way that it would interpret a signal from a traditional keyboard when a key is pressed. A keyboard created in this fashion on a touch sensitive display is sometimes called a “soft keyboard.”